Quantum annealing devices are actively pursued by several academic labs and companies such as Google and D-Wave Systems, with uncertain quantum speedup.
For example, the D-Wave quantum computer is a commercially available hardware device that is designed and built to implement quantum annealing physically.
It is an analog computing device based on superconducting quantum bits (also called qubits) to process the annealing procedure and solve combinatorial optimization problems
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The D-Wave computers have been used to solve simple optimization problems in graphs and networks, machine learning, artificial intelligence, and computational biology
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As an example, the lowest energy alignment of a protein is considered as its preferred state, and protein folding is to find the lowest energy point in its energy landscape; the D-Wave computers can be arranged to manipulate qubits to reach their lowest energy state and solve the folding problem of a simple protein
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